Real Estate Properties - Summary of Balance Sheet Information for all Properties Classified as Held for sale (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Liabilities related to properties held for sale	$ 169	$ 0
Held-for-sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Real estate properties	19,568
Rents receivable, net of allowance for doubtful accounts of $159	21
Other assets, net	758
Properties held for sale	20,347
Rent collected in advance	10
Security deposits	159
Liabilities related to properties held for sale	169
Allowance for doubtful accounts	$ 159

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Amount classified as assets attributable to disposal group held for sale or disposed of.

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